US8977183B2 - Cleaning device, and image carrier unit and image forming apparatus having same - Google Patents
Cleaning device, and image carrier unit and image forming apparatus having same Download PDFInfo
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- US8977183B2 US8977183B2 US13/778,613 US201313778613A US8977183B2 US 8977183 B2 US8977183 B2 US 8977183B2 US 201313778613 A US201313778613 A US 201313778613A US 8977183 B2 US8977183 B2 US 8977183B2
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- toner
- image carrier
- cylindrical face
- rotating
- contact
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G21/00—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge
- G03G21/0005—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge for removing solid developer or debris from the electrographic recording medium
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G21/00—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge
- G03G21/0005—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge for removing solid developer or debris from the electrographic recording medium
- G03G21/0011—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge for removing solid developer or debris from the electrographic recording medium using a blade; Details of cleaning blades, e.g. blade shape, layer forming
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G21/00—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge
- G03G21/0005—Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge for removing solid developer or debris from the electrographic recording medium
- G03G21/007—Arrangement or disposition of parts of the cleaning unit
Definitions
- the present disclosure relates to a cleaning device for cleaning an image carrier which carries a toner image, and an image carrier unit and an image forming apparatus having such a cleaning device.
- an image forming apparatus for forming an image on a sheet known is technology of a sheet passing through a transfer nip part, which is formed between a photoreceptor drum and a transfer roller, in a direction from down to up. A toner image is formed on the photoreceptor drum, and the toner image is transferred to the sheet at the transfer nip part.
- the image forming apparatus further includes a fixing unit, and the sheet to which the toner image was transferred is subject to fixation processing by the fixing unit, and then discharged.
- a cleaning device is disposed facing the photoreceptor drum in order to clean the residual toner on the photoreceptor drum after the toner image is transferred at the transfer nip part.
- the cleaning device that is disposed on the further downstream side in the rotating direction of the photoreceptor drum than the transfer nip part is often disposed above the photoreceptor drum.
- the cleaning device is disposed above an image carrier including a rotating axis, and a cylindrical face which rotates in one direction around the rotating axis and carries a toner image, and cleans the cylindrical face.
- the cleaning device includes a case, a rotating member, a sheet member, and a cover member.
- the rotating member is provided in the case, includes a peripheral face which comes into contact with the cylindrical face above the rotating axis in a cross section view that is orthogonal to the rotating axis, is rotatively driven in a same direction as the image carrier at a contact position which comes into contact with the cylindrical face, and recovers a toner which has attached on the image carrier.
- the sheet member is provided in the case, extends, in the cross section view, from a position that is above the rotating axis and separated from the cylindrical face toward a direction approaching a straight line that connects the rotating axis of the image carrier and the contact position of the rotating member, and includes a leading end which comes into contact with the cylindrical face on a side that is further upstream in the rotating direction of the image carrier than the rotating member.
- the cover member is provided in the case so as to cover an upside of the sheet member, extends from a position that is separated from the cylindrical face in the cross section view toward a direction approaching the straight line, and reaches a position above the leading end of the sheet member.
- the image carrier unit includes the foregoing cleaning device, and the image carrier.
- the image carrier is disposed facing the rotating member.
- the image forming apparatus includes the foregoing cleaning device, the image carrier, and a developing device.
- the image carrier is disposed facing the rotating member.
- the developing device supplies a toner to the cylindrical face of the image carrier.
- FIG. 1 is a perspective view showing the appearance of the image forming apparatus according to one embodiment of the present disclosure
- FIG. 2 is a lateral cross section showing the internal structure of the image forming apparatus according to one embodiment of the present disclosure
- FIG. 3 is a lateral cross section showing the internal structure of the image carrier unit according to one embodiment of the present disclosure
- FIG. 4 is a lateral cross section showing the internal structure of the image carrier unit to be compared with the present disclosure
- FIG. 5 is a schematic diagram explaining a state where the toner is accumulated on the toner seal of FIG. 4 ;
- FIG. 6 is a schematic diagram explaining the state where the leading end of the toner seal of FIG. 4 is lifting due to a clump of paper dust;
- FIG. 7 is an enlarged cross section of a part of FIG. 4 ;
- FIG. 8 is an enlarged cross section of a part of FIG. 3 ;
- FIG. 9 is an enlarged lateral cross section of a part of the image carrier unit according to another embodiment of the present disclosure.
- FIG. 1 is a perspective view showing the appearance of the image forming apparatus 1 according to one embodiment of the present disclosure.
- FIG. 2 is a lateral cross section showing the internal structure of the image forming apparatus 1 according to one embodiment of the present disclosure.
- the image forming apparatus may also be a copier, a facsimile machine, or a multi-function product having their functions, or an image forming apparatus which forms color images.
- the image forming apparatus 1 includes a body housing 10 which has a substantially rectangular case structure, and a paper feeding unit 20 , an image forming unit 30 , a fixing unit 40 and a toner container 50 which are housed in the body housing 10 .
- a front cover 11 is provided on a front face side of the body housing 10 and a rear cover 12 is provided on a rear face side of the body housing 10 , respectively.
- the rear cover 12 is a cover that is opened upon a sheet jam or for maintenance.
- the image forming unit 30 and the fixing unit 40 can be respectively removed from the rear face side of the body housing 10 as a result of the rear cover 12 being opened.
- a left cover 12 L ( FIG. 1 ) is provided to a side face of the body housing 10 and a right cover 12 R (not shown in FIG.
- FIG. 1 is provided to a side that is opposite to the left cover 12 L, respectively, in a manner of extending in the vertical direction.
- An inlet 12 La for incorporating air into the body housing 10 is provided to the front side portion of the left cover 12 L.
- the top face of the body housing 10 has a paper discharging unit 13 to which a sheet, after an image is formed thereon, is discharged.
- Various devices for executing image formation are mounted in an internal space S ( FIG. 2 ) which is demarcated by the front cover 11 , the rear cover 12 , the left cover 12 L, the right cover 12 R, and the paper discharging unit 13 .
- the paper feeding unit 20 includes a paper feeding cassette 21 for housing the sheets that were subject to the image forming process ( FIG. 2 ). A part of the paper feeding cassette 21 protrudes further forward from the front face of the body housing 10 . Of the paper feeding cassette 21 , the top face of the portion that is housed in the body housing 10 is covered by a paper feeding cassette top panel 21 U.
- the paper feeding cassette 21 has a sheet housing space where a bundle of sheets is housed, and a lift plate for lifting the bundle of sheets for paper feeding.
- a sheet supplying unit 21 A is provided to the top part on the rear end side of the paper feeding cassette 21 .
- the sheet supplying unit 21 A is provided with a paper feed roller 21 B for supplying, one sheet at a time, the uppermost sheet of the sheet bundle in the paper feeding cassette 21 .
- the image forming unit 30 performs the image forming process of forming a toner image on the sheet that is fed from the paper feeding unit 20 .
- the image forming unit 30 includes a photoreceptor drum 31 (image carrier), and a charging device 32 , an exposure device (not shown in FIG. 2 ), a developing device 33 , a transfer roller 34 and a cleaning device 35 which are disposed around the photoreceptor drum 31 .
- the image forming unit 30 is disposed between the left cover 12 L and the right cover 12 R.
- the photoreceptor drum 31 includes a rotating axis 31 A, and a cylindrical face 31 B which rotates around the rotating axis 31 A ( FIG. 3 ). An electrostatic latent image is formed on the cylindrical face 31 B, and a toner image according to the electrostatic latent image is carried on the cylindrical face 31 B.
- a photoreceptor drum configured from an amorphous silicon (a-Si)-based material may be used as the photoreceptor drum 31 .
- the charging device 32 is used for uniformly charging the surface of the photoreceptor drum 31 , and includes a charge roller which comes into contact with the photoreceptor drum 31 .
- the cleaning device 35 includes a cleaning blade and the like.
- the cleaning device 35 cleans the toner that became attached to the peripheral face of the photoreceptor drum 31 after the transfer of the toner image, and conveys the toner to a recovery device not shown.
- the photoreceptor drum 31 , the charging device 32 , and the cleaning device 35 are configured integrally as a drum unit 31 H (refer to FIG. 3 ) (image carrier unit).
- the cleaning device 35 and the drum unit 31 H will be described later in detail.
- the exposure device includes optical components such as a laser light source, a mirror, and a lens.
- the exposure device forms an electrostatic latent image on the cylindrical face 31 B of the photoreceptor drum 31 by irradiating a laser beam that was modulated based on the image data provided from an external device such as a personal computer.
- the developing device 33 supplies a toner to the cylindrical face 31 B of the photoreceptor drum 31 for developing the electrostatic latent image and forming the toner image on the photoreceptor drum 31 .
- the developing device 33 includes a developing roller 331 for carrying the toner to be supplied to the photoreceptor drum 31 , and a first agitating screw 332 and a second agitating screw 333 for circulating and conveying, while agitating, the developer in a development housing not shown.
- the transfer roller 34 is a roller for transferring, onto the sheet, the toner image formed on the cylindrical face 31 B of the photoreceptor drum 31 .
- the transfer roller 34 comes into contact with the cylindrical face 31 B of the photoreceptor drum 31 , and forms a transfer nip part TP ( FIG. 3 ).
- a transfer bias of reverse polarity to the toner is applied to the transfer roller 34 .
- the fixing unit 40 performs fixation processing of fixing the transferred toner image onto the sheet.
- the fixing unit 40 includes a fixing roller 41 internally having a heat source, and a pressure roller 42 pressed against the fixing roller 41 and forms a fixation nip part with the fixing roller 41 .
- the toner image is fixed onto the sheet based on the heating by the fixing roller 41 and the pressurization by the pressure roller 42 .
- the toner container 50 stores the toner to be supplied to the developing device 33 .
- the toner container 50 includes a container body 51 which is the main location where the toner is stored, a cylindrical part 52 which protrudes from the bottom part of one side face of the container body 51 , a cover member 53 which covers the other side face of the container body 51 , and a rotating member 54 which conveys the toner housed inside the container.
- the toner stored in the toner container 50 is supplied inside the developing device 33 from a toner discharge outlet 521 provided to the bottom tip face of the cylindrical part 52 by the rotating member 54 by rotatively driven.
- the container top panel 50 H which covers the upside of the toner container 50 is positioned below the paper discharging unit 13 (refer to FIG. 2 ).
- the body housing 10 internally includes a main feeding path 22 F and a reverse feeding path 22 B for feeding the sheets.
- the main feeding path 22 F extends from the sheet supplying unit 21 A of the paper feeding unit 20 to the paper discharge outlet 14 , which is provided in a manner of facing the top face of the body housing 10 , via the image forming unit 30 and the fixing unit 40 .
- the reverse feeding path 22 B is a feeding path for returning the sheet subject to one-side printing to the upstream side of the image forming unit 30 in the main feeding path 22 F upon performing both-side printing to the sheet.
- the main feeding path 22 F (sheet feeding path) is extended in a manner of passing the transfer nip part, which is formed from the photoreceptor drum 31 and the transfer roller 34 , in a direction of down to up.
- a resist roller pair 23 is disposed on a side of the main feeding path 22 F that is further upstream than the transfer nip part TP.
- the sheet is once stopped by the resist roller pair 23 and the skew correction of the sheet is performed. Subsequently, at a predetermined timing for transferring the image, the sheet is once again fed toward the transfer nip part TP.
- a plurality of transport rollers for transporting the sheets are disposed and, for example, a paper discharge roller pair 24 is disposed near the paper discharge outlet 14 .
- the reverse feeding path 22 B is formed between the outer face of the reversal unit 25 and the inner face of the rear cover 12 of the body housing 10 .
- the transfer roller 34 and one roller of the resist roller pair 23 are mounted on the inner face of the reversal unit 25 .
- the rear cover 12 and the reversal unit 25 are respectively turnable around the axis of the fulcrum point 121 provided to the lower ends thereof.
- FIG. 3 is an enlarged cross section of the drum unit 31 H according to this embodiment.
- FIG. 4 is an enlarged cross section of the drum unit 31 HW for comparison with the drum unit 31 H. Note that FIG. 3 and FIG. 4 are illustrated as diagrams which invert the left-right direction on the plane of paper (front-back direction of the image forming apparatus 1 ) in FIG. 2 .
- the drum unit 31 H includes a photoreceptor drum 31 , a charging device 32 , and a cleaning device 35 .
- the drum unit 31 H includes a pair of side plates (supports) not shown at either end in the left-right direction (direction that is orthogonal to the plane of paper of FIG. 3 ).
- the photoreceptor drum 31 is rotatably supported by the pair of side plates.
- the charging device 32 and the cleaning device 35 are supported facing the photoreceptor drum 31 by the pair of side plates.
- the photoreceptor drum 31 is rotatively driven in the arrow DP direction in FIG. 3 .
- the drum unit 31 H includes a fixing part (not shown) disposed on the side plate.
- the fixing part is fixed to the body housing 10 of the image forming apparatus 1 . Consequently, the position of the drum unit 31 H is fixed in the image forming apparatus 1 .
- the fixing part is configured from a fastening hole to which a screw is fastened.
- the charging device 32 is disposed further on the front side than the photoreceptor drum 31 .
- the charging device 32 includes a charge roller 321 , a cleaning roller 322 , and a charge housing 32 H.
- the charge housing 32 H has a substantial U-shape in a cross section view that is orthogonal to the rotating axis 31 A of the photoreceptor drum 31 .
- a charge roller 321 and a cleaning roller 322 are respectively rotatably supported in the charge housing 32 H.
- the charge roller 321 is a roller member in which the surface thereof is configured from a rubber material. A charged voltage is applied to the charge roller 321 from a bias application part not shown. The charge roller 321 is rotated by following the photoreceptor drum 31 as a result of coming into contact with the cylindrical face 31 B of the photoreceptor drum 31 . The cylindrical face 31 B of the photoreceptor drum 31 is uniformly charged by the charge roller 321 to which a charged voltage was applied.
- the cleaning roller 322 comes into contact with the charge roller 321 , and rotates together with the charge roller 321 with a linear velocity difference.
- the cleaning roller 322 is a brush roller formed from conductive nylon fiber.
- toner and extraneous matter become attached to the surface of the charge roller 321 .
- discharge products become attached to the surface of the charge roller 321 .
- the cleaning roller 322 rotating with a linear velocity difference while contacting the charge roller 321 , the toner and extraneous matter attached to the surface of the charge roller 321 can be suitably removed.
- the cleaning device 35 is disposed above the photoreceptor drum 31 .
- the cleaning device 35 includes a cleaner housing 35 H, a cleaning blade 351 , a conveying screw 352 , and a polishing roller 353 .
- the cleaning device 35 includes a scraper 354 , a scraper holder 355 , and a top part seal 356 .
- the cleaning device 35 includes a first plate 357 , a protective sheet 361 , a second plate 358 , a cover seal 359 , and a toner seal 360 .
- the cleaner housing 35 H is a case which supports the respective members in the cleaning device 35 .
- the cleaning device 35 is disposed so as to cover the upside of the photoreceptor drum 31 and the charging device 32 .
- the front portion of the cleaner housing 35 H is disposed above the charge roller 321 .
- the center portion of the cleaner housing 35 H in the front-back direction has a shape that protrudes cylindrically upward.
- the rear portion of the cleaner housing 35 H is demarcated by a housing rear wall 35 H 1 (wall part).
- the housing rear wall 35 H 1 is a wall part that extends in a vertical direction.
- the housing rear wall 35 H 1 is disposed to face the polishing roller 353 described later.
- the lower end of the housing rear wall 35 H 1 is disposed at a given spacing from the cylindrical face 31 B of the photoreceptor drum 31 .
- the lower end of the housing rear wall 35 H 1 is disposed above the toner seal 360 described later at a given spacing and covers the upside of the toner seal 360 .
- the cleaning blade 351 is disposed in the horizontal direction along the base part of the cleaner housing 35 H.
- the cleaning blade 351 is a plate-shaped member configured from a rubber material.
- the cleaning blade 351 is supported by the blade holder 351 H.
- the blade holder 351 H is an L-shaped metal plate member in the cross section view.
- the center portion of the blade holder 351 H is fixed to the cleaner housing 35 H by the first fixing screw 351 B.
- the cleaning blade 351 and the blade holder 351 H are fixed using an adhesive. Consequently, a fixing end of the cleaning blade 351 is formed. Meanwhile, the tip of the cleaning blade 351 is a free end, and comes into contact with the cylindrical face 31 B of the photoreceptor drum 31 .
- the tip of the cleaning blade 351 comes into contact with the cylindrical face 31 B on a side that is further downstream in the rotating direction (arrow DP direction) of the photoreceptor drum 31 than the polishing roller 353 described later. Consequently, the toner remaining on (attached to) the cylindrical face 31 B of the photoreceptor drum 31 is removed with the tip of the cleaning blade 351 .
- the conveying screw 352 is rotatably supported by the cleaner housing 35 H above the cleaning blade 351 .
- the conveying screw 352 includes a shaft, and a spiral fin member disposed around the shaft.
- the conveying screw 352 conveys, in an axial direction of the rotating axis 31 A of the photoreceptor drum 31 , the recovered toner PT that was wiped by the cleaning blade 351 and accumulated on the cleaning blade 351 .
- the polishing roller 353 is disposed at the rear of the conveying screw 352 .
- the polishing roller 353 includes a peripheral face which comes into contact with the cylindrical face 31 B positioned higher than the rotating axis 31 A of the photoreceptor drum 31 .
- the polishing roller 353 comes into contact with the cylindrical face 31 B of the photoreceptor drum 31 from the transfer nip part TP up to a position that is immediately above the rotating axis 31 A of the photoreceptor drum 31 .
- the polishing roller 353 comes into contact with the cylindrical face 31 B immediately above the rotating axis 31 A of the photoreceptor drum 31 or on a side that is slightly further upstream in the rotating direction of the photoreceptor drum 31 than the position that is immediately above the rotating axis 31 A of the photoreceptor drum 31 .
- the position on the cylindrical face 31 B where the polishing roller 353 comes into contact is defined as the contact position CP.
- the polishing roller 353 is a rubber roller in which the surface thereof was subject to roughening treatment.
- the polishing roller 353 rotates by following the photoreceptor drum 31 while coming into contact with the cylindrical face 31 B of the photoreceptor drum 31 (arrow DC).
- the polishing roller 353 recovers the toner attached to the cylindrical face 31 B of the photoreceptor drum 31 . Moreover, the polishing roller 353 grinds extraneous matter such as discharge products that became attached to the cylindrical face 31 B of the photoreceptor drum 31 . Here, as a result of attaching a predetermined amount of toner to the peripheral face of the polishing roller 353 , removal performance (grind performance) of the discharge products can be improved.
- the scraper 354 (restricting member) is a plate-shaped member extending in the up-down direction (vertical direction).
- the scraper 354 is configured from an SUS plate having a thickness of 0.05 mm.
- the lower end of the scraper 354 comes into contact with the peripheral face of the polishing roller 353 .
- the lower end of the scraper 354 comes into contact with the peripheral face of the polishing roller 353 opposite to the rotating direction (arrow DC direction, against direction) of the polishing roller 353 .
- the scraper 354 coming into contact with the peripheral face of the polishing roller 353 based on predetermined elastic force, the amount of toner attached to the peripheral face of the polishing roller 353 is restricted. Consequently, the amount of toner that becomes attached to the peripheral face of the polishing roller 353 becomes uniform, and variation in the removal performance of the discharge products by the polishing roller 353 is thereby inhibited.
- the scraper holder 355 is disposed so as to cover the upside of the polishing roller 353 .
- the scraper holder 355 is configured from a bent plate member.
- the center part of the scraper holder 355 extends in the horizontal direction.
- the front portion of the scraper holder 355 is bent downward, and supports the scraper 354 .
- the rear portion of the scraper holder 355 is bent rearward and downward along the peripheral face of the polishing roller 353 .
- the top part seal 356 is fixed on the scraper holder 355 .
- One end of the top part seal 356 is supported at the center part of the scraper holder 355 , and the other end of the top part seal 356 is disposed to protrude forward from the scraper holder 355 .
- the top part seal 356 has a function of blocking the toner that becomes airborne upon the toner attached to the peripheral face of the polishing roller 353 being scraped by the scraper 354 .
- the first plate 357 is disposed facing the housing rear wall 35 H 1 of the cleaner housing 35 H.
- the first plate 357 is a plate member extending in the up-down direction.
- the center part of the first plate 357 in the up-down direction is fixed to the housing rear wall 35 H 1 by the second fixing screw 357 B.
- the first plate top part 357 T as the upper side end part of the first plate 357 is bent rearward.
- the first plate bottom part 357 S as the lower side end part of the first plate 357 is bent forward.
- the first plate bottom part 357 S is disposed facing the lower end of the housing rear wall 35 H 1 and so as to be inserted between the lower end of the housing rear wall 35 H 1 and the cylindrical face 31 B of the photoreceptor drum 31 .
- the first plate bottom part 357 S is disposed above the toner seal 360 described later at a given spacing, and covers the toner seal 360 .
- the protective sheet 361 is configured from a thin plate-shaped elastic material.
- the protective sheet 361 is a urethane sheet having a thickness of 100 ⁇ m.
- the protective sheet 361 is disposed on the top face of the bent first plate bottom part 357 S.
- the protective sheet 361 is configured from a protective base end 361 T that is bonded with and fixed to the top face of the first plate bottom part 357 S, and a protective leading end 361 S which protrudes further forward than the first plate bottom part 357 S.
- the protective base end 361 T forms the fixing end of the protective sheet 361
- the protective leading end 361 S forms the free end of the protective sheet 361 .
- the second plate 358 is disposed facing the first plate 357 at the rear of the first plate 357 .
- the second plate 358 is a plate member extending in the up-down direction.
- the second plate top part 358 T as the upper end part of the second plate 358 is bent in the rear direction, and thereafter bent to curve upward.
- the second plate 358 is fixed to the cleaner housing 35 H with a fixing screw not shown outside the paper feeding region.
- the second plate bottom part 358 S as the lower end part of the second plate 358 is disposed in a manner of bending forward.
- the second plate bottom part 358 S is disposed parallel to the first plate bottom part 357 S at the rear side of the first plate bottom part 357 S.
- the cover seal 359 extends in the up-down direction along the second plate 358 .
- the upper portion of the cover seal 359 is bonded with and fixed to the second plate 358 , and forms the fixing end of the cover seal 359 .
- the lower portion of the cover seal 359 is disposed to protrude downward from the second plate 358 , and forms the free end of the cover seal 359 .
- the leading end on the lower side of the cover seal 359 is disposed close to cylindrical face 31 B of the photoreceptor drum 31 .
- the toner seal 360 (sheet member) extends in a horizontal direction along the second plate bottom part 358 S of the second plate 358 .
- the toner seal 360 is a urethane sheet having a thickness of 100 ⁇ m.
- the rear portion of the toner seal 360 is bonded with and fixed to the second plate bottom part 358 S, and forms the fixing end 360 F of the toner seal 360 .
- the leading end 360 S ( FIG. 8 ) of the front portion of the toner seal 360 forms the free end of the toner seal 360 and comes into contact with the cylindrical face 31 B of the photoreceptor drum 31 .
- the leading end 360 S of the toner seal 360 comes into contact with the cylindrical face 31 B at a position that is higher than the rotating axis 31 A and on a side that is further upstream in the rotating direction of the photoreceptor drum 31 than the polishing roller 353 in a cross section view that is orthogonal to the rotating axis 31 A of the photoreceptor drum 31 .
- the toner seal 360 comes into contact with the cylindrical face 31 B toward a direction that approaches the reference straight line RL that connects the rotating axis 31 A and the contact position CP of the polishing roller 353 from the second plate bottom part 358 S as the position separated from the cylindrical face 31 B of the photoreceptor drum 31 in a cross section view that is orthogonal to the rotating axis 31 A of the photoreceptor drum 31 .
- the toner seal 360 has a function of preventing the toner from leaking from the inside of the cleaner housing 35 H.
- the first plate bottom part 357 S of the first plate 357 and the housing rear wall 35 H 1 are disposed above the front portion of the toner seal 360 .
- the first plate bottom part 357 S and the housing rear wall 35 H 1 are disposed above the toner seal 360 such that the toner seal 360 protrudes further toward the front side (polishing roller 353 side) than the fixing end 360 F fixed to the second plate bottom part 358 S.
- the foregoing protective sheet 361 is disposed above the toner seal 360 .
- the protective sheet 361 is provided to the first plate bottom part 357 S so as to cover the upside of the toner seal 360 .
- the protective sheet 361 extends, in the cross section view that is orthogonal to the rotating axis 31 A of the photoreceptor drum 31 , from the first plate bottom part 357 S as a position that is separated from the cylindrical face 31 B of the photoreceptor drum 31 toward a direction which approaches the reference straight line RL that connects the rotating axis 31 A and the contact position CP of the polishing roller 353 , until reaching the position 361 M above the leading end 360 S of the front portion of the toner seal 360 ( FIG. 8 ).
- the protective sheet 361 extends so as to protrude further toward the direction of approaching the reference straight line RL than the position 361 M above the leading end 360 S. Moreover, the protective sheet 361 extends parallel to the direction that the toner seal 360 extends.
- An electrostatic latent image is formed on the photoreceptor drum 31 in which its peripheral face was uniformly charged by the charge roller 321 of the charging device 32 by an exposure device not shown on a side that is further downstream in the rotating direction than the charging device 32 . Subsequently, the electrostatic latent image is visualized as a toner image by the developing device 33 ( FIG. 2 ) disposed below the photoreceptor drum 31 .
- the photoreceptor drum 31 is rotated in a direction of down to up at the transfer nip part TP.
- the toner image formed on the photoreceptor drum 31 is transferred on the sheet that is transported in a direction of down to up at the transfer nip part TP.
- the transfer nip part TP a part of the toner image that was transferred to the sheet will remain on the photoreceptor drum 31 as residual toner.
- the residual toner on the photoreceptor drum 31 is conveyed to the region where the cleaning device 35 faces the photoreceptor drum 31 in a direction of down to up in response to the rotation of the photoreceptor drum 31 .
- a part of the residual toner that was conveyed to the region facing the cleaning device 35 becomes attached to the peripheral face of the polishing roller 353 . Moreover, the residual toner that did not become attached to the peripheral face of the polishing roller 353 is wiped by the cleaning blade 351 .
- a part of the toner attached to the peripheral face of the polishing roller 353 is wiped by the scraper 354 .
- the toner that remains on the peripheral face of the polishing roller 353 as a result of exceeding the leading end of the scraper 354 circles above the polishing roller 353 while passing through the region facing the scraper holder 355 and the housing rear wall 35 H 1 .
- the toner attached to the peripheral face of the polishing roller 353 becomes separate from the polishing roller 353 .
- the toner separated from the polishing roller 353 is dispersed to a region surrounded by the scraper holder 355 , the housing rear wall 35 H 1 and the peripheral face of the photoreceptor drum 31 .
- FIG. 4 is a diagram for comparison with the cleaning device 35 according to an embodiment of the present disclosure, and is a cross section of a drum unit 31 HW having a cleaning device 35 W.
- the cleaning device 35 W includes a toner seal 380 .
- the toner seal 380 is configured, as with the toner seal 360 , from a urethane sheet disposed in the horizontal direction.
- the rear portion of the toner seal 380 is fixed and supported by the first plate bottom part 357 S.
- the front portion of the toner seal 380 configures a free end and comes into contact with the peripheral face of the photoreceptor drum 31 .
- the cleaning device 35 W differs from the foregoing cleaning device 35 in that it does not includes the foregoing protective sheet 361 above the toner seal 380 .
- FIG. 5 and FIG. 6 are diagrams showing the state around the toner seal 380 in the foregoing case.
- FIG. 7 is an enlarged view of a part of the drum unit 31 HW ( FIG. 4 ) within the portion schematically shown in FIG. 5 and FIG. 6 .
- the toner residue TN dispersed on the toner seal 380 is accumulated in the form of a mountain shape. Consequently, based on the own weight of the toner residue TN, pressing force as shown with the arrow H is applied to the toner seal 380 .
- the paper dust attached to the surface of the sheet P is transferred to the peripheral face of the photoreceptor drum 31 upon the toner image being transferred to the sheet P at the transfer nip part TP.
- the paper dust attached to the peripheral face of the photoreceptor drum 31 is conveyed toward the tip of the toner seal 380 in response to the rotation of the photoreceptor drum 31 .
- toner residue TN is not formed on the toner seal 380
- the tip of the toner seal 380 is in contact with the peripheral face of the photoreceptor drum based on low contact pressure.
- the paper dust conveyed to the photoreceptor drum 31 passes between the tip of the toner seal 380 and the peripheral face of the photoreceptor drum 31 , and is recovered by the polishing roller 353 and the cleaning blade 351 .
- the tip 381 of the toner seal 380 will lift off the peripheral face of the photoreceptor drum 31 in correspondence with the portion where the clump PD exist in the axial direction of the rotating axis 31 A of the photoreceptor drum 31 ( FIG. 6 ). Consequently, the toner TN 1 will begin to leak from the toner residue TN. The toner TN 1 will fall along the peripheral face of the photoreceptor drum 31 according to gravity (arrow DT of FIG. 6 , arrow D 7 of FIG. 7 ). In addition, the toner TN 1 that reached the transfer nip part TP becomes attached to the sheet P that was transported to the transfer nip part TP. Consequently, the sheet P is contaminated by the toner.
- the toner seal 380 generates a clump PD of paper dust and the sheet P is contaminated by the toner.
- the protective sheet 361 is suitably disposed above the toner seal 360 .
- FIG. 8 is an enlarged view of the periphery of the toner seal 360 and the protective sheet 361 in FIG. 3 .
- the foregoing protective sheet 361 is disposed above the toner seal 360 .
- the protective sheet 361 is provided to the first plate bottom part 357 S so as to cover the upside of the toner seal 360 .
- the protective sheet 361 extends, in a cross section view that is orthogonal to the rotating axis 31 A of the photoreceptor drum 31 , from the first plate 357 side to the position 361 M above the leading end 360 S of the toner seal 360 in a direction which approaches the reference straight line RL ( FIG. 3 ) that connects the rotating axis 31 A and the contact position CP of the polishing roller 353 .
- the protective sheet 361 extends in a manner of protruding further toward a direction of approaching the reference straight line RL ( FIG. 3 ) than the position 361 M above the leading end 360 S of the toner seal 360 .
- the toner that was dispersed from the polishing roller 353 accumulates on the protective sheet 361 as shown in FIG. 8 .
- the toner accumulated on the protective sheet 361 is guided to the rotating face 31 B side of the photoreceptor drum 31 based on the rotative force of the polishing roller 353 .
- the protective sheet 361 is deformable based on elastic force, the toner will not be hardened pressed (rammed down) between the peripheral face of the polishing roller 353 and the protective sheet 361 .
- the protective leading end 361 S of the protective sheet 361 being deformed downward in accordance with the rotative force of the polishing roller 353 , the transfer of the toner to the photoreceptor drum 31 side is promoted.
- the protective sheet 361 effectively inhibits the toner from becoming accumulated on the toner seal 360 .
- the protective sheet 361 is disposed to protrude even further than the upward position 361 M of the leading end 360 S of the toner seal 360 .
- the toner that was dispersed from the rotating member it becomes difficult for the toner that was dispersed from the rotating member to reaching the toner seal 360 .
- the first plate bottom part 357 S and the housing rear wall 35 H 1 are disposed above the toner seal 360 to protrude further toward the front side (polishing roller 353 side) than the fixing end 360 F ( FIG. 3 ) in which the toner seal 360 is fixed to the second plate bottom part 358 S.
- the first plate bottom part 357 S of the first plate 357 is disposed so as to cover the upside of the toner seal 360 .
- the lower end of the housing rear wall 35 H 1 is disposed above the first plate bottom part 357 S.
- the housing rear wall 35 H 1 is disposed, in a manner of facing the polishing roller 353 , above the leading end 360 S of the toner seal 360 and on the rear side of the peripheral face of the polishing roller 353 .
- the toner that is dispersed from the peripheral face of the polishing roller 353 toward the rear in response to the rotation of the polishing roller 353 will collide with the housing rear wall 35 H 1 and fall downward. Accordingly, the housing rear wall 35 H 1 tends to guide the toner onto the protective sheet 361 .
- the protective sheet 361 tends to deform due to elastic force.
- the protective sheet 361 can be deformed downward based on the own weight of the toner that is accumulated on the protective sheet 361 . Consequently, the toner accumulated on the protective sheet 361 tends to be guided toward the cylindrical face 31 B of the photoreceptor drum 31 .
- one end of the toner seal 360 is the fixing end 360 F that is fixed to the cleaner housing 35 H, and the other end of the toner seal 360 is the leading end 360 S configured from a free end.
- the leading end 360 S of the toner seal 360 deforms easily as a free end. Consequently, the space between the cleaner housing 35 H and the cylindrical face 31 B of the photoreceptor drum 31 can more easily be blocked by the leading end 360 S of the toner seal 360 .
- the cleaning blade 351 is disposed on a side that is further downstream in the rotating direction of the photoreceptor drum 31 than the polishing roller 353 .
- the toner which became attached to the photoreceptor drum 31 can be removed with accuracy.
- the toner can be recovered by the polishing roller 353 and the cleaning blade 351 .
- the extraneous matter that became attached to the cylindrical face 31 B of the photoreceptor drum 31 is effectively ground by the polishing roller 353 .
- the scraper 354 restricts the amount of toner to become attached to the peripheral face of the polishing roller 353 .
- variation in the promoted grinding effect can be inhibited by the position on the peripheral face of the polishing roller 353 .
- the polishing roller 353 comes into contact with the cylindrical face 31 B of the photoreceptor drum 31 from the transfer nip part TP to the position immediately above the rotating axis 31 A of the photoreceptor drum 31 . Consequently, the leading end 360 S of the toner seal 360 comes into contact with the cylindrical face 31 B below the position CP where the polishing roller 353 comes into contact with the cylindrical face 31 B and on the upstream side in the rotating direction of the photoreceptor drum 31 . Thus, the toner that was dispersed from the polishing roller 353 tends to fall on the toner seal 360 .
- the protective sheet 361 is disposed so as to cover the upside of the toner seal 360 . Accordingly, it is possible to prevent the toner from becoming accumulated on the toner seal 360 . Thus, it becomes difficult for the contact pressure of the toner seal 360 against the photoreceptor drum 31 to increase, and it is possible to inhibit the occurrence of toner leakage from the leading end 360 S of the toner seal 360 .
- drum unit 31 H and the image forming apparatus 1 including the cleaning device 35 were explained above, but the present disclosure is not limited thereto, and may take on, for instance, the modified embodiments described below.
- FIG. 9 is an enlarged cross section of the cleaning device 35 V including the protective sheet 362 according to another embodiment of the present disclosure.
- the protective sheet 362 includes a tip guiding part 361 S 1 at the tip of the protective leading end 362 S.
- the tip guiding part 361 S 1 is formed as a result of the tip of the protective leading end 362 S being bent downward.
- the tip guiding part 361 S 1 is disposed to incline toward the cylindrical face 31 B of the photoreceptor drum 31 .
- the toner accumulated on the protective sheet 362 moves to the cylindrical face 31 B of the photoreceptor drum 31 as a result of being guided by the tip guiding part 361 S 1 .
- the function of the protective sheet 362 protecting (covering) the upside of the toner seal 360 is favorably maintained.
- polishing roller 353 and the cleaning blade 351 are disposed on a side that is further downstream in the rotating direction of the photoreceptor drum 31 than the toner seal 360 , but the present disclosure is not limited thereto.
- the polishing roller 353 may also be a cleaning roller which cleans the surface of the photoreceptor drum 31 .
- the cleaning blade 351 may be disposed on a side that is further downstream in the rotating direction of the photoreceptor drum 31 than the cleaning roller, or the mode may be such that the cleaning blade 351 is not provided.
- the protective sheet 361 as the cover member is configured from a thin plate-shaped elastic member, but the present disclosure is not limited thereto.
- the protective sheet 361 may also be a part of the member which configures the cleaner housing 35 H.
- the protective sheet 361 (cover member) may also be configured from the first plate bottom part 357 S of the first plate 357 .
- the cleaning device 35 including the toner seal 360 is provided to the drum unit 31 H, but the present disclosure is not limited thereto.
- the cleaning device 35 including the toner seal 360 may also be mounted on the image forming apparatus 1 individually.
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Abstract
Description
Claims (12)
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JP2012043416A JP5393823B2 (en) | 2012-02-29 | 2012-02-29 | Cleaning device, image carrier unit including the same, and image forming apparatus |
JP2012-043416 | 2012-02-29 |
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US20130223904A1 US20130223904A1 (en) | 2013-08-29 |
US8977183B2 true US8977183B2 (en) | 2015-03-10 |
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US13/778,613 Active 2033-03-24 US8977183B2 (en) | 2012-02-29 | 2013-02-27 | Cleaning device, and image carrier unit and image forming apparatus having same |
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JP5740328B2 (en) * | 2012-02-29 | 2015-06-24 | 京セラドキュメントソリューションズ株式会社 | Cleaning device, image carrier unit including the same, and image forming apparatus |
JP6283492B2 (en) * | 2013-10-09 | 2018-02-21 | 京セラドキュメントソリューションズ株式会社 | Cleaning device and image forming apparatus having the same |
US9927731B2 (en) * | 2016-04-04 | 2018-03-27 | Kyocera Document Solutions Inc. | Image forming apparatus having an electrifying member for electrifying an image carrier |
JP6848568B2 (en) * | 2017-03-21 | 2021-03-24 | 富士ゼロックス株式会社 | Transfer device and image forming device using it |
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US20130223904A1 (en) | 2013-08-29 |
JP5393823B2 (en) | 2014-01-22 |
JP2013181996A (en) | 2013-09-12 |
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